/*
 * ====================================================================
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */

package com.feilong.lib.org.apache.http;

import java.io.Serializable;
import java.net.InetAddress;
import java.util.Locale;

import com.feilong.lib.org.apache.http.annotation.Contract;
import com.feilong.lib.org.apache.http.annotation.ThreadingBehavior;
import com.feilong.lib.org.apache.http.util.Args;
import com.feilong.lib.org.apache.http.util.LangUtils;

/**
 * Holds all of the variables needed to describe an HTTP connection to a host.
 * This includes remote host name, port and scheme.
 *
 * @since 4.0
 */
@Contract(threading = ThreadingBehavior.IMMUTABLE)
public final class HttpHost implements Cloneable,Serializable{

    private static final long   serialVersionUID    = -7529410654042457626L;

    /** The default scheme is "http". */
    public static final String  DEFAULT_SCHEME_NAME = "http";

    /** The host to use. */
    protected final String      hostname;

    /** The lowercase host, for {@link #equals} and {@link #hashCode}. */
    protected final String      lcHostname;

    /** The port to use, defaults to -1 if not set. */
    protected final int         port;

    /** The scheme (lowercased) */
    protected final String      schemeName;

    protected final InetAddress address;

    /**
     * Creates {@code HttpHost} instance with the given scheme, hostname and port.
     *
     * @param hostname
     *            the hostname (IP or DNS name)
     * @param port
     *            the port number.
     *            {@code -1} indicates the scheme default port.
     * @param scheme
     *            the name of the scheme.
     *            {@code null} indicates the
     *            {@link #DEFAULT_SCHEME_NAME default scheme}
     */
    public HttpHost(final String hostname, final int port, final String scheme){
        super();
        this.hostname = Args.containsNoBlanks(hostname, "Host name");
        this.lcHostname = hostname.toLowerCase(Locale.ROOT);
        if (scheme != null){
            this.schemeName = scheme.toLowerCase(Locale.ROOT);
        }else{
            this.schemeName = DEFAULT_SCHEME_NAME;
        }
        this.port = port;
        this.address = null;
    }

    /**
     * Creates {@code HttpHost} instance with the default scheme and the given hostname and port.
     *
     * @param hostname
     *            the hostname (IP or DNS name)
     * @param port
     *            the port number.
     *            {@code -1} indicates the scheme default port.
     */
    public HttpHost(final String hostname, final int port){
        this(hostname, port, null);
    }

    /**
     * Creates {@code HttpHost} instance from string. Text may not contain any blanks.
     *
     * @since 4.4
     */
    public static HttpHost create(final String s){
        Args.containsNoBlanks(s, "HTTP Host");
        String text = s;
        String scheme = null;
        final int schemeIdx = text.indexOf("://");
        if (schemeIdx > 0){
            scheme = text.substring(0, schemeIdx);
            text = text.substring(schemeIdx + 3);
        }
        int port = -1;
        final int portIdx = text.lastIndexOf(":");
        if (portIdx > 0){
            try{
                port = Integer.parseInt(text.substring(portIdx + 1));
            }catch (final NumberFormatException ex){
                throw new IllegalArgumentException("Invalid HTTP host: " + text);
            }
            text = text.substring(0, portIdx);
        }
        return new HttpHost(text, port, scheme);
    }

    /**
     * Creates {@code HttpHost} instance with the default scheme and port and the given hostname.
     *
     * @param hostname
     *            the hostname (IP or DNS name)
     */
    public HttpHost(final String hostname){
        this(hostname, -1, null);
    }

    /**
     * Creates {@code HttpHost} instance with the given scheme, inet address and port.
     *
     * @param address
     *            the inet address.
     * @param port
     *            the port number.
     *            {@code -1} indicates the scheme default port.
     * @param scheme
     *            the name of the scheme.
     *            {@code null} indicates the
     *            {@link #DEFAULT_SCHEME_NAME default scheme}
     *
     * @since 4.3
     */
    public HttpHost(final InetAddress address, final int port, final String scheme){
        this(Args.notNull(address, "Inet address"), address.getHostName(), port, scheme);
    }

    /**
     * Creates a new {@link HttpHost HttpHost}, specifying all values.
     * Constructor for HttpHost.
     *
     * @param address
     *            the inet address.
     * @param hostname
     *            the hostname (IP or DNS name)
     * @param port
     *            the port number.
     *            {@code -1} indicates the scheme default port.
     * @param scheme
     *            the name of the scheme.
     *            {@code null} indicates the
     *            {@link #DEFAULT_SCHEME_NAME default scheme}
     *
     * @since 4.4
     */
    public HttpHost(final InetAddress address, final String hostname, final int port, final String scheme){
        super();
        this.address = Args.notNull(address, "Inet address");
        this.hostname = Args.notNull(hostname, "Hostname");
        this.lcHostname = this.hostname.toLowerCase(Locale.ROOT);
        if (scheme != null){
            this.schemeName = scheme.toLowerCase(Locale.ROOT);
        }else{
            this.schemeName = DEFAULT_SCHEME_NAME;
        }
        this.port = port;
    }

    /**
     * Creates {@code HttpHost} instance with the default scheme and the given inet address
     * and port.
     *
     * @param address
     *            the inet address.
     * @param port
     *            the port number.
     *            {@code -1} indicates the scheme default port.
     *
     * @since 4.3
     */
    public HttpHost(final InetAddress address, final int port){
        this(address, port, null);
    }

    /**
     * Creates {@code HttpHost} instance with the default scheme and port and the given inet
     * address.
     *
     * @param address
     *            the inet address.
     *
     * @since 4.3
     */
    public HttpHost(final InetAddress address){
        this(address, -1, null);
    }

    /**
     * Copy constructor for {@link HttpHost HttpHost}.
     *
     * @param httphost
     *            the HTTP host to copy details from
     */
    public HttpHost(final HttpHost httphost){
        super();
        Args.notNull(httphost, "HTTP host");
        this.hostname = httphost.hostname;
        this.lcHostname = httphost.lcHostname;
        this.schemeName = httphost.schemeName;
        this.port = httphost.port;
        this.address = httphost.address;
    }

    /**
     * Returns the host name.
     *
     * @return the host name (IP or DNS name)
     */
    public String getHostName(){
        return this.hostname;
    }

    /**
     * Returns the port.
     *
     * @return the host port, or {@code -1} if not set
     */
    public int getPort(){
        return this.port;
    }

    /**
     * Returns the scheme name.
     *
     * @return the scheme name
     */
    public String getSchemeName(){
        return this.schemeName;
    }

    /**
     * Returns the inet address if explicitly set by a constructor,
     * {@code null} otherwise.
     * 
     * @return the inet address
     *
     * @since 4.3
     */
    public InetAddress getAddress(){
        return this.address;
    }

    /**
     * Return the host URI, as a string.
     *
     * @return the host URI
     */
    public String toURI(){
        final StringBuilder buffer = new StringBuilder();
        buffer.append(this.schemeName);
        buffer.append("://");
        buffer.append(this.hostname);
        if (this.port != -1){
            buffer.append(':');
            buffer.append(Integer.toString(this.port));
        }
        return buffer.toString();
    }

    /**
     * Obtains the host string, without scheme prefix.
     *
     * @return the host string, for example {@code localhost:8080}
     */
    public String toHostString(){
        if (this.port != -1){
            //the highest port number is 65535, which is length 6 with the addition of the colon
            final StringBuilder buffer = new StringBuilder(this.hostname.length() + 6);
            buffer.append(this.hostname);
            buffer.append(":");
            buffer.append(Integer.toString(this.port));
            return buffer.toString();
        }
        return this.hostname;
    }

    @Override
    public String toString(){
        return toURI();
    }

    @Override
    public boolean equals(final Object obj){
        if (this == obj){
            return true;
        }
        if (obj instanceof HttpHost){
            final HttpHost that = (HttpHost) obj;
            return this.lcHostname.equals(that.lcHostname) && this.port == that.port && this.schemeName.equals(that.schemeName)
                            && (this.address == null ? that.address == null : this.address.equals(that.address));
        }
        return false;
    }

    /**
     * @see java.lang.Object#hashCode()
     */
    @Override
    public int hashCode(){
        int hash = LangUtils.HASH_SEED;
        hash = LangUtils.hashCode(hash, this.lcHostname);
        hash = LangUtils.hashCode(hash, this.port);
        hash = LangUtils.hashCode(hash, this.schemeName);
        if (address != null){
            hash = LangUtils.hashCode(hash, address);
        }
        return hash;
    }

    @Override
    public Object clone() throws CloneNotSupportedException{
        return super.clone();
    }

}
